Another 24% also reported issues with compiling data from multiple sites across their business, and one in 10 didn't fully understand what was required of them to complete registration.

Head of business energy services at npower, Dave Lewis, said: "If collecting the required information together was problematic, then going forward, many may well find the ongoing obligations of the scheme equally challenging.

"This confusion could also explain the high number of businesses that have left completing CRC registration to the last minute and are unsure if they have submitted the correct data.

"We worked with a number of businesses to support their registration and part of the problem is that many failed to appreciate the full scale of the task."

The Environment Agency, the body overseeing the introduction of the scheme, have admitted many organisations found the CRC complicated and have promised to simplify it.

Eon boss Johannes Teysson has lashed out at politicians for failing to rescue the EU emissions trading system (ETS). Anyone who claims Europe is a pioneer of climate protection "should be ashamed", he told the German daily newspaper Suddeutsche Zeitung.